Hi . A friend of mine is rebuilding a rs1800. We are wondering if any of you guys know the best place for new panels. We have new arch repair panels and a new rear panel but need the piece that goes between the rear panel and quarter panel. I have seen complete quarters with them on but would rather a repair panel as I already have the arches now. It's the piece that the air vents fit in either side of the rear (back) panel. Thanks kyle